From patchwork Mon Jun 17 10:53:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aradhya Bhatia X-Patchwork-Id: 13700504 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C76F6C2BB9A for ; Mon, 17 Jun 2024 10:54:00 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 099A710E343; Mon, 17 Jun 2024 10:53:58 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=ti.com header.i=@ti.com header.b="Lk2I81kP"; dkim-atps=neutral Received: from fllv0015.ext.ti.com (fllv0015.ext.ti.com [198.47.19.141]) by gabe.freedesktop.org (Postfix) with ESMTPS id D1AD510E339 for ; Mon, 17 Jun 2024 10:53:40 +0000 (UTC) Received: from fllv0034.itg.ti.com ([10.64.40.246]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 45HArMCQ061400; Mon, 17 Jun 2024 05:53:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1718621602; bh=1KYYm54tymbTNJp06YFH1DJi8RZj+jpPyPwKIKxm3dU=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=Lk2I81kPobYFyCf0wGEMk1b0ccYIqdUbHMZCKp0uHpWQ1M3wp4w0PRbrDItAzvAXw tgtmfPMG9v1+Fb+DRmIjsT1ulM0C/xg66wgN2xiTXtTr5n0dlw45YD7k+zPycNxr32 JQaFbP2MY1MUOr6GRFFa1UCGI87uk43PPUvYZLkY= Received: from DLEE107.ent.ti.com (dlee107.ent.ti.com [157.170.170.37]) by fllv0034.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 45HArM8O055905 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 17 Jun 2024 05:53:22 -0500 Received: from DLEE105.ent.ti.com (157.170.170.35) by DLEE107.ent.ti.com (157.170.170.37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23; Mon, 17 Jun 2024 05:53:21 -0500 Received: from lelvsmtp6.itg.ti.com (10.180.75.249) by DLEE105.ent.ti.com (157.170.170.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2507.23 via Frontend Transport; Mon, 17 Jun 2024 05:53:21 -0500 Received: from localhost (uda0496377.dhcp.ti.com [172.24.227.31]) by lelvsmtp6.itg.ti.com (8.15.2/8.15.2) with ESMTP id 45HArLXH106126; Mon, 17 Jun 2024 05:53:21 -0500 From: Aradhya Bhatia To: Dmitry Baryshkov , Tomi Valkeinen , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Jyri Sarha , Thomas Zimmermann , David Airlie , Daniel Vetter CC: DRI Development List , Linux Kernel List , Dominik Haller , Sam Ravnborg , Thierry Reding , Kieran Bingham , Nishanth Menon , Vignesh Raghavendra , Praneeth Bajjuri , Udit Kumar , Devarsh Thakkar , Jayesh Choudhary , Jai Luthra , Aradhya Bhatia Subject: [PATCH v3 06/10] drm/bridge: cdns-dsi: Reset the DCS write FIFO Date: Mon, 17 Jun 2024 16:23:07 +0530 Message-ID: <20240617105311.1587489-7-a-bhatia1@ti.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240617105311.1587489-1-a-bhatia1@ti.com> References: <20240617105311.1587489-1-a-bhatia1@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Allow the DCS Write FIFO in the cdns-dsi controller to reset before any DCS packet is transmitted to the DSI sink device. The DCS FIFO reset is optional. Not all panels require it. But at least one of the DSI based panel that uses Ilitek ILI9881C (DSI to DPI bridge) doesn't work with without this reset. Signed-off-by: Aradhya Bhatia --- drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c index 05d2f4cc50da..87fdd07ca0bc 100644 --- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c +++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c @@ -1037,6 +1037,9 @@ static ssize_t cdns_dsi_transfer(struct mipi_dsi_host *host, cdns_dsi_init_link(dsi); + /* Reset the DCS Write FIFO */ + writel(0x00, dsi->regs + DIRECT_CMD_FIFO_RST); + ret = mipi_dsi_create_packet(&packet, msg); if (ret) goto out;